Justine Vanden Heuvel, Associate Professor of Viticulture, called for vineyards to participate in a project on palissage. She asked growers to experiment with this method and share their observations with her and her graduate student Justin France.
This report describes the experimental setup and results with one of the two types of palissage; wrapping the shoots around the top wire.
At ‘De Achthoeven’ vineyard two grape varieties were choosen, Marechal Foch and Solaris, based on their vigorous growth and tendency to form lateral shoots.
Both grape varieties showed a reduction in growth of lateral shoots in the vertical part of the canopy when palissage was applied. The effect is larger with the Marechal Foch.
Although no diseases were found (up to the time of writing this report), the dense canopy with palissage is a concern. The additional weight causes stretching of the top wire. When palissage is choosen, the supporting trellis system needs to be strenghtened.
No reduction in the time required for attending the vines was observed.
For the grape variety for which separate measurements were performed at harvest, no significant differences in quantities, sugar levels and acidity were observed between the two rows.
Two grape varieties, Marechal Foch and Solaris, were chosen for the experiment because of their vigorous growth and strong tendency to grow axillary shoots and form a dense foliage. Both grapes grow on SO4 rootstock.
The four rows, with each 10 grapes, are planted in North-South direction, with prevailing winds from the South-west. The two outer rows were chosen for palissage, the two inner rows for the ‘control’ (traditionally pruned) vines.
The type of palissage is with the shoot tips wrapped horizontally along the top wire at 2m.
Soil type is a so-called “Enkeerdgrond” (approx. 40-50 cm humus-rich brown-colored layer of soil on sharp sand. These soils are the result of fertilization of poor earth with manure and sod during centuries of human occupation.). This soil-type is not very fertile, a bit acidic (pH approx 6) and minerals are washed out easily. The drainage is very good.
The growing season started half of April, a bit ahead of the long-time average, after a long, but mild winter. The months of May and June were a bit cooler than average, but with a lot of sun and little rain. July was hotter than average and again dry.
A major part of the 2015 growing season in The Netherlands was amongst the 5% driest years since measurements began in 1705. But this changed at the end of July. The first serious rain (30mm in one day) came at the end of July and in the second half of August. From then on, we had sunny periods and perdiods with intense showers. During the rainy periods the temperatures were more or less normal, resulting in increased risk of diseases in the vineyard.
From September onward, this type of weather with alternating sunny and dry periods continued. The temperatures were slightly lower than the long-time average.
The amount of rain and sun during the growing season are shown in the next two figures.
The rainfall deficit, averaged over the entire Netherlands, is shown in the following figure (figure 1) by the black line. The blue line shows the median.
The next figure (figure 2) shows the Huglin-index, a measure for the temperature during the growing season. The Huglin-index is similar, but not identical, to the Growing Degree Days measure. The plot shows the long time average (dark red line), the curve for this year (light red) and a shifted curve of the long time average that goes through the current value (dark red dotted line) and which shows the difference in days between the current value of the Huglin-index and the long time average.
The plot also shows the Huglin-index at harvest for some hybrid and common grape varieties.
The “Huglin” plot also shows the different growth phases for the Rondo grape, which is an “early” grape variety like the Solaris and Marechal Foch varieties (the data are based on private measurements between 2009-2014). These varieties all have approximately equal bud-break. The Solaris ripens about one to two weeks earlier, the Marechal Foch ripens about one or two weeks later than the Rondo.
| BBCH-scale | Dutch | English | M.Foch | Solaris |
|---|---|---|---|---|
| 05 | wol-stadium | wool stage | 10-4-2015 | 10-4-2015 |
| 09 | knoppen breken | bud break | 22-4-2015 | 23-4-2015 |
| 11 | 1e blad | first leave | 25-4-2015 | 27-4-2015 |
| 13 | 3e blad | third leave | 1-5-2015 | 5-5-2015 |
| 15 | 5e blad | fifth leave | 11-5-2015 | 13-5-2015 |
| 61 | 10% bloei | 10% flowering | 6-6-2015 | 10-6-2015 |
| 68 | 80% bloei | 80% flowering | 14-6-2015 | 25-6-2015 |
| 73 | korrelgrootte | groat-sized berries | 24-6-2015 | 30-6-2015 |
| 83 | verkleuring | ‘veraison’ | 10-8-2015 | 30-7-2015 |
| 89 | oogst | harvest | 11-10-2015 | 20-9-2015 |
The first shoots reached the top wire around June 5th. The first hedging took place on July 10th. At that time, the shoots were 100-150cm ‘above’ the top wire.
Both the ‘inner’ rows were hedged manually with a hedge trimmer. Both the ‘outer’ rows were wrapped manually.
The following table shows the time spent on hedging and wrapping:
| variety | method | time/vine (minutes) | ease |
|---|---|---|---|
| M.Foch | hedging | 1.5 a 2.0 | 2 |
| M.Foch | wrapping | 2 | 5 |
| Solaris | hedging | 1 | 2 |
| Solaris | wrapping | 2.5 | 5 |
with the ease of applying the method described on a scale 1 to 10, where 1 is technically easy and quick, where 5 took some technical learning and time, and where 10 is difficult and time consuming.
Notes:
The following photo’s show the rows before and after the pruning activities.
| variety | before | after |
|---|---|---|
| M.Foch | ||
| Solaris |
The following photo shows a close-up of the wrapped Marechal Foch.